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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 270 insertions, 0 deletions

diff --git a/src/corelib/kernel/qpointer.cpp b/src/corelib/kernel/qpointer.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+    \class QPointer
+    \brief The QPointer class is a template class that provides guarded pointers to QObject.
+
+    \ingroup objectmodel
+
+
+    A guarded pointer, QPointer<T>, behaves like a normal C++
+    pointer \c{T *}, except that it is automatically set to 0 when the
+    referenced object is destroyed (unlike normal C++ pointers, which
+    become "dangling pointers" in such cases). \c T must be a
+    subclass of QObject.
+
+    Guarded pointers are useful whenever you need to store a pointer
+    to a QObject that is owned by someone else, and therefore might be
+    destroyed while you still hold a reference to it. You can safely
+    test the pointer for validity.
+
+    Qt also provides QSharedPointer, an implementation of a reference-counted
+    shared pointer object, which can be used to maintain a collection of
+    references to an individual pointer.
+
+    Example:
+
+    \snippet doc/src/snippets/pointer/pointer.cpp 0
+    \dots
+    \snippet doc/src/snippets/pointer/pointer.cpp 1
+    \snippet doc/src/snippets/pointer/pointer.cpp 2
+
+    If the QLabel is deleted in the meantime, the \c label variable
+    will hold 0 instead of an invalid address, and the last line will
+    never be executed.
+
+    The functions and operators available with a QPointer are the
+    same as those available with a normal unguarded pointer, except
+    the pointer arithmetic operators (\c{+}, \c{-}, \c{++}, and
+    \c{--}), which are normally used only with arrays of objects.
+
+    Use QPointers like normal pointers and you will not need to read
+    this class documentation.
+
+    For creating guarded pointers, you can construct or assign to them
+    from a T* or from another guarded pointer of the same type. You
+    can compare them with each other using operator==() and
+    operator!=(), or test for 0 with isNull(). You can dereference
+    them using either the \c *x or the \c x->member notation.
+
+    A guarded pointer will automatically cast to a \c T *, so you can
+    freely mix guarded and unguarded pointers. This means that if you
+    have a QPointer<QWidget>, you can pass it to a function that
+    requires a QWidget *. For this reason, it is of little value to
+    declare functions to take a QPointer as a parameter; just use
+    normal pointers. Use a QPointer when you are storing a pointer
+    over time.
+
+    Note that class \c T must inherit QObject, or a compilation or
+    link error will result.
+
+    \sa QSharedPointer, QObject, QObjectCleanupHandler
+*/
+
+/*!
+    \fn QPointer::QPointer()
+
+    Constructs a 0 guarded pointer.
+
+    \sa isNull()
+*/
+
+/*!
+    \fn QPointer::QPointer(T* p)
+
+    Constructs a guarded pointer that points to same object that \a p
+    points to.
+*/
+
+/*!
+    \fn QPointer::QPointer(const QPointer<T> &p)
+
+    Copies one guarded pointer from another. The constructed guarded
+    pointer points to the same object that \a p points to (which may
+    be 0).
+*/
+
+/*!
+    \fn QPointer::~QPointer()
+
+    Destroys the guarded pointer. Just like a normal pointer,
+    destroying a guarded pointer does \e not destroy the object being
+    pointed to.
+*/
+
+/*!
+    \fn QPointer<T>& QPointer::operator=(const QPointer<T> &p)
+
+    Assignment operator. This guarded pointer will now point to the
+    same object that \a p points to.
+*/
+
+/*!
+    \fn QPointer<T> & QPointer::operator=(T* p)
+
+    Assignment operator. This guarded pointer will now point to the
+    same object that \a p points to.
+*/
+
+/*!
+    \fn T* QPointer::data() const
+    \since 4.4
+
+    Returns the pointer to the object being guarded.
+*/
+
+/*!
+    \fn bool QPointer::isNull() const
+
+    Returns \c true if the referenced object has been destroyed or if
+    there is no referenced object; otherwise returns false.
+*/
+
+/*!
+    \fn T* QPointer::operator->() const
+
+    Overloaded arrow operator; implements pointer semantics. Just use
+    this operator as you would with a normal C++ pointer.
+*/
+
+/*!
+    \fn T& QPointer::operator*() const
+
+    Dereference operator; implements pointer semantics. Just use this
+    operator as you would with a normal C++ pointer.
+*/
+
+/*!
+    \fn QPointer::operator T*() const
+
+    Cast operator; implements pointer semantics. Because of this
+    function you can pass a QPointer\<T\> to a function where a T*
+    is required.
+*/
+
+/*!
+    \fn bool operator==(const T *o, const QPointer<T> &p)
+    \relates QPointer
+
+    Equality operator. Returns true if \a o and the guarded
+    pointer \a p are pointing to the same object, otherwise
+    returns false.
+
+*/
+/*!
+    \fn bool operator==(const QPointer<T> &p, const T *o)
+    \relates QPointer
+
+    Equality operator. Returns true if \a o and the guarded
+    pointer \a p are pointing to the same object, otherwise
+    returns false.
+
+*/
+/*!
+    \fn bool operator==(T *o, const QPointer<T> &p)
+    \relates QPointer
+
+    Equality operator. Returns true if \a o and the guarded
+    pointer \a p are pointing to the same object, otherwise
+    returns false.
+
+*/
+/*!
+    \fn bool operator==(const QPointer<T> &p, T *o)
+    \relates QPointer
+
+    Equality operator. Returns true if \a o and the guarded
+    pointer \a p are pointing to the same object, otherwise
+    returns false.
+
+*/
+/*!
+    \fn bool operator==(const QPointer<T> &p1, const QPointer<T> &p2)
+    \relates QPointer
+
+    Equality operator. Returns true if the guarded pointers \a p1 and \a p2
+    are pointing to the same object, otherwise
+    returns false.
+
+*/
+
+
+/*!
+    \fn bool operator!=(const T *o, const QPointer<T> &p)
+    \relates QPointer
+
+    Inequality operator. Returns true if \a o and the guarded
+    pointer \a p are not pointing to the same object, otherwise
+    returns false.
+*/
+/*!
+    \fn bool operator!=(const QPointer<T> &p, const T *o)
+    \relates QPointer
+
+    Inequality operator. Returns true if \a o and the guarded
+    pointer \a p are not pointing to the same object, otherwise
+    returns false.
+*/
+/*!
+    \fn bool operator!=(T *o, const QPointer<T> &p)
+    \relates QPointer
+
+    Inequality operator. Returns true if \a o and the guarded
+    pointer \a p are not pointing to the same object, otherwise
+    returns false.
+*/
+/*!
+    \fn bool operator!=(const QPointer<T> &p, T *o)
+    \relates QPointer
+
+    Inequality operator. Returns true if \a o and the guarded
+    pointer \a p are not pointing to the same object, otherwise
+    returns false.
+*/
+/*!
+    \fn bool operator!=(const QPointer<T> &p1, const QPointer<T> &p2)
+    \relates QPointer
+
+    Inequality operator. Returns true if  the guarded pointers \a p1 and
+    \a p2 are not pointing to the same object, otherwise
+    returns false.
+*/